The present invention relates to control of air conditioners, and more particularly to an electric control method and apparatus for an automobile air conditioner for controlling the cooling ability of the air conditioner to possibly reduce the power losses of a prime engine of the automobile.
In a conventional automobile air conditioner, a compressor is driven by the prime engine to compress refrigerant medium supplied into an evaporator so as to cool the air flowing into a passenger compartment to be conditioned. The compressor is equipped with an electromagnetic clutch mechanism which is arranged to be deactivated under the condition where the outside ambient temperature is below a predetermined value (for instance, approximately 15.degree. C.) or an air-blend door is maintained in a position to cut-off the cooled air flowing into the passenger compartment from the evaporator. This serves to reduce unnecessary torque losses of the prime engine. In this control of the compressor, even if the actual in-car temperature is adjusted to a desired value, the electromagnetic clutch mechanism may not be deactivated in spite of the condition noted above. As a result, effective control of the compressor may not be conducted in accordance with adjustment of the actual in-car temperature, causing still unnecessary power torque losses of the prime engine.